What is a Peritoneal Equilibration Test?

A Peritoneal Equilibration Test known as a PET test, is used to find out whether waste toxins pass quickly or slowly from the person’s bloodstream and into the dialysis fluid. If the toxins move quickly, the person is called a ‘high or fast transporter’. If the toxins move slowly, the person is a ‘low or slow transporter’.

The reason why ‘high Transporters’ have poor water removal is because the water and glucose from the PD fluid are absorbed into the body, if the fluid is not drained out after a 2-3 hour dwell. Waste, water and glucose can move quickly in both directions.

A PET test helps PD staff to decide whether your dialysis would be improved by leaving your PD fluid in the abdomen for longer or shorter periods of time. A nurse usually performs the test in hospital. A full PET test takes around 5 hours to complete and involves doing a CAPD exchange using a 2.27% glucose bag. Samples of PD fluid, and blood are taken at set times. Some Units do a mini PET test, and only one blood and PD sample are taken when the PD fluid is drained out after a 4-hour dwell in the abdomen. The person is usually asked to save all the PD fluid they drain out and all the urine they pass in the 24-hour period prior to the PET. The waste from the 24-hour period is tested and this is known as a Peritoneal Function Test.

NKF Controlled Document No. 245, What is a Peritoneal Equilibration Test?, written 26 January 2001. Last reviewed 19 October 2009.

The National Kidney Federation cannot accept responsibility for information provided. The above is for guidance only. Patients are advised to seek further information from their own doctor.

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